Question:
How do I know when a watermelon is ready to harvest?Answer:
Harvest when the underside or "belly" of the melon turns from a greenish white to buttery yellow or cream. This color change is especially pronounced on the dark green-skinned varieties. It is often less noticeable on lighter-skinned watermelons. In addition, the fruit tends to lose its slick appearance on top and becomes dull when ripe.
The browning of the pig's tail (light green, curly tendril attached to the vine near the melon) is another option for determining ripeness. In some varieties, the pig's tail may turn brown 7 to 10 days before the melon is ripe making this method of determining ripeness unreliable in some varieties. Often the browning of the pig tail can be used in conjunction with the change in belly color to determine ripeness, especially for those varieties whose belly color change is not easily seen.
Thumping or tapping the melon is generally not a good indicator of ripeness. Rapping an immature melon with your knuckles produces a metallic ring. A ripe melon gives off a hollow or dull ring. Most individuals, however, have difficulty differentiating between the sounds.
When harvesting watermelons, leave 2 inches of the stem on the fruit. Watermelons can be stored at room temperature for about one week and for two to three weeks at 50 to 60 degrees Fahrenheit.
Learn more in this article: Growing Watermelon in the Home Garden.